44205401TH Rev.1
174 /
Oki Data CONFIDENTIAL
7. Troubleshooting and repair procedure
7.5.2. (11) Fuser unit error (error 170 to 177)
(11-1) Error occurs immediately after the power is turned on.
Check item Check work
Action to be taken
at NG
(11-1-1) Thermistor is defective Note)
Upper thermistor,
lower thermistor,
frame thermistor
Check the respective thermistors if they are
shorted or opened internally.
Check the resistance value at the connector pins
in the bottom of the fuser unit.
(Refer to section 8.1 Resistance check (fuser
unit).)
Replace the
fuser unit.
If any attempt of
using new fuser
unit as a trial
is going to be
made, be sure to
use the System
Maintenance
Menu FUSE
KEEP MODE.
Installed condition of
fuser unit.
Check if the fuser nit is pressed in until the
connector in the bottom of the fuser unit is surely
connected.
Re-set the fuser
unit.
Note! Service calls 171 error and 171 error can occur when the printer temperature
is below 0
. Turn on the power again after the printer temperature has
increased.
(11-2) Error occurs approx. 1 minute after the power is turned on.
Check item Check work
Action to be taken
at NG
(11-2-1) Temperature increase of fuser unit
Thermostat, halogen
lamp
Heater of the fuser unit is controlled of its
temperature. Check if the fuser unit gets hot or
not by touching it with hands.
If the fuser unit temperature does not increase
and remains cold, check that the resistance
between pin-1 and pin-6 of connector A, and that
in between pin-1 and pin-6 of connector B of the
two connectors is in the range of several ohms to
several ten ohms respectively. (Refer to section
8.1 Resistance value (fuser unit).)
Replace the
fuser unit.
If any attempt of
using new fuser
unit as a trial
is going to be
made, be sure to
use the System
Maintenance
Menu FUSE
KEEP MODE.
Check item Check work
Action to be taken
at NG
(11-2-2) Temperature increase of fuser unit
Installation position
of the upper
thermistor
Check if the upper thermistor is installed in the
far position from the specified position or not
causing detection of the lower temperature than
the actual temperature of fuser unit.
Remove the heater cover, and check warpage of
sensor by visual inspection.
Replace the
fuser unit.
If any attempt of
using new fuser
unit as a trial
is going to be
made, be sure to
use the System
Maintenance
Menu FUSE
KEEP MODE.
Installation position
of the lower
thermistor
The lower thermister must be installed while
contacting with the fuser unit. Check if the lower
thermister is installed in the far position from the
specified position or not causing detection of the
lower temperature than the actual temperature of
fuser unit.
Replace the
fuser unit.
If any attempt of
using new fuser
unit as a trial
is going to be
made, be sure to
use the System
Maintenance
Menu FUSE
KEEP MODE.
(11-2-3) AC power input to the halogen lamp
AC power voltage
from the low voltage
power supply
Chec
k if the AC v
oltage for heater is normally
supplied or not.
Power supply CN2 connector , between pin-1
and pin-2, and between pin-3 and pin-4.
Replace the low
voltage power
supply.
Heater ON signal
that is output from
PU to the low voltage
power supply
Check that the heater ON signal goes active at
the warming up timing, or not.
"L" active while ON.
Power connector
of the CU/PU board,
between pin-14 and pin-15.
Replace the
CU/PU board.